As energy plays a central role in the world development, it represents as well a major challenge for sustainable development. Today, more than 80% of the primary energy consumption is based on fossil fuels and the share is likely to remain high in the future. Even if technology developments will reduce the specific consumption, the world energy demand is likely to increase in line with its population. Energy and material efficiency and the integration of the renewable resources will therefore have to play a major role for sustainable development. The challenge concerns not only the technologies at the conversion and useful energy level, but also the energy management and infrastructures. The 2000 W per capita society initiative launched by the Board of the Swiss Institutes of Technology targets the identification of the major technological breakthroughs to reduce the per capita primary energy use of Switzerland by two-thirds within five decades. This study examined the energy saving potentials in the complete conversion chain “from primary energy to energy services” in the main sectors of economy: buildings, transport and industry. The report highlights the possible benefits which could be obtained from new materials, new technologies and an intensification of product and capital use. The systems integration appeared to be of prime importance in order to valorise the exergy potentials of the energy resources. The report emphasizes the political responsibility of developing the enabling society infrastructure: not only for the energy distribution (electrical, gas or heating networks) but also for the information technology, the appropriate regulations, the education and for the necessary integration of the lifetimes of the manufactured artifacts in the pathway to the 2000 W per capita society.